How to distribute an application that relies on DLL's for 32-bit and 64-bit machines

Question

I have an application that uses a 3rd party jar (utils.jar), which calls a 3rd party DLL (utils.dll). The jar file manages calls to DLL including the name of the DLL. There is a 32-bit version and a 64-bit version of the DLL.

Currently, the application can only run on 32-bit machines. When I try to run it on a 64-bit machine, it tells me

Can't load IA 32-bit .dll on a AMD 64-bit platform

When I replace the 32-bit dll with the 64-bit, it works fine. I don't want to maintain two separate releases if I can avoid it (one using 32-bit library, the other using 64-bit library). Is there a way to build the application so that it can figure out which version of the library it needs to use?

Our projects are built using Ant, though I can explore other alternatives if necessary.

Answer 1

You have to create an additonal ant target such that it builds always a x32 and a x64 variant of your application.

I don't want to maintain two separate releases

If the ant your skript always produce both deliverys that its not much addional effort.

Answer 2

When you do loadLibary you could compose the library name with the System.getProperty("os.arch") . So, you bundle all dlls, and the related version will be chosen at run-time.

Answer 3

For deploying Java desktop apps., the best option is usually to install the app. using Java Web Start ¹ . JWS works on Windows, OS X & *nix.

1. JWS provides many appealing features including, but not limited to, splash screens, desktop integration, file associations, automatic update (including lazy downloads and programmatic control of updates), partitioning of natives & other resource downloads by platform, architecture or Java version, configuration of run-time environment (minimum J2SE version, run-time options, RAM etc.), easy management of common resources using extensions..